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R Web Scraping Quick Start Guide

You're reading from   R Web Scraping Quick Start Guide Techniques and tools to crawl and scrape data from websites

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Product type Paperback
Published in Oct 2018
Publisher Packt
ISBN-13 9781789138733
Length 114 pages
Edition 1st Edition
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Olgun Aydin Olgun Aydin
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Olgun Aydin
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Regular expression language (Regex)

Regular expressions are extremely useful when they are used to extract information from any text by searching for a specific sequence of ASCII or Unicode characters. The web is frequently used in search operations. One of the most impressive features of Regex is that it can be used in almost all programming languages. Basically, a regular expression is a formula that helps explain a text. RegEx's name comes from the mathematical theory underlying the idea. It is usually shortened to regex or regexp.

You can use regular expressions with a text bean that you can usually access using your programming language. If it is known how a Regex engine works, it will be easier to generate regexes. It will be easy to understand why you cannot do what you expect with a regular expression and write more complex expressions.

There are basically only two...

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